In the field of refrigerating and heating technology, an electronic expansion valve is a component used to control a flow rate of refrigerant in a refrigerating and heating device, and the working process of the electronic expansion valve is generally illustrated as follows. With a coil device being energized or de-energized, a vale needle regulates an opening of a valve port, thereby regulating the flow rate of the refrigerant.
In the conventional technology, an electronic expansion valve is disclosed in a Chinese Patent Application Publication No. “CN102454819A”. Reference is made to FIG. 1, which is a schematic view showing the structure of an electronic expansion valve in the conventional technology.
As shown in FIG. 1, the electronic expansion valve includes a valve seat 1′ and a housing 2′, and the housing 2′ is fixedly supported on the valve seat 1′, therefore, the relative position between the housing 2′ and the valve seat 1′ is fixed. A rotatable magnet 3′ is provided inside the housing 2′, the magnet 3′ is fixedly connected to a screw rod 4′, and the screw rod 4′ cooperates with a nut 5′ by screw threads. The nut 5′ has a lower end fixed to the valve seat 1′, therefore, the relative position between the nut 5′ and the valve seat 1′ is fixed. The electronic expansion valve further includes a stop component, the stop component includes a spindle 6′1 which is fixed with respect to the valve seat 1′, a spring guide rail 6′2 sleeved on the spindle 6′1, and a sliding ring 6′3 configured to cooperate with the spring guide rail 6′2. In such structure, an upper portion of the nut 5′ forms the spindle 6′1, and the spring guide rail 6′2 is sleeved on an outer wall of the upper portion of the nut 5′.
As show in FIG. 1, in the above structure, a top portion of the magnet 3′ is provided with a connecting seat 3′1, the connecting seat 3′1 is connected to a stop rod 6′4 extending downwards, and the stop rod 6′4 cooperates with an extending portion 6′3a of the sliding ring 6′3. As the magnet 3′ rotates, the stop rod 6′4 cooperates with the extending portion 6′3a to drive the sliding ring 6′3 to rotate along the spring guide rail 6′2, and the scope of rotation of the sliding ring 6′3 is limited between an upper limit position and a lower limit position of the spring guide rail 6′2, thereby limiting a number of turns of rotation of the magnet 3′.
However, the electronic expansion valve of the above structure has the following defects:
Firstly, the stop rod 6′4 is connected to an inner wall of the connecting seat 3′1, and is assembled inside the magnet 3′, thus the assembly process is difficult, and the assembly cost is high. Furthermore, the reliability of connection of the stop rod 6′4 is low, and after working for a period of time, the stop rod 6′4 is apt to fall out.
Secondly, the extending portion 6′3a of the sliding ring 6′3 is required to extend in a radial direction by an enough length so as to cooperate with the stop rod 6′4, and meanwhile, it is further required to avoid an interference between the extending portion 6′3a and the inner wall of the magnet 3′, thus the magnet 3′ is required to have a large radial dimension, which not only increases the material cost, but also is adverse to the minimization of the product.